# Haploid like spermatid generation by transplantation of neonatal mouse testicular tissue into the epididymal fat of castrated adult mouse

## TL;DR

This study shows that transplanting neonatal mouse testicular tissue into adult mice can support sperm cell development, offering hope for preserving fertility in cancer survivors.

## Contribution

The study demonstrates that epididymal fat provides suitable conditions for spermatogenesis in grafted testicular tissue.

## Key findings

- A gradient of germ cells, from spermatogonia to elongated spermatids, was observed in grafted tissues.
- Meiotic and post-meiotic genes and proteins were upregulated in both fresh and frozen grafted groups.
- No significant differences in apoptosis, necrosis, or hormone levels were found between grafted and control groups.

## Abstract

Many cancer survivors may experience irreversible infertility due to
chemotherapy treatment for childhood cancer. In this study, spermatogenesis
development was evaluated following the grafting of fresh and frozen-thawed
testicular tissue from neonatal mice to the epididymal fat of adult
mice.

After bilateral castration of recipient mice, fresh or frozen-thawed neonatal
testis tissues were grafted into the epididymal fat of the mice. Grafted
testicular tissue was evaluated eight weeks after implantation using H&E
staining, real-time PCR, immunofluorescence staining, and TUNEL assay. Blood
was drawn from recipient mice to determine testosterone, FSH, and LH
levels.

A gradient of different types of germ cells, from spermatogonia to elongated
spermatids was observed. The upregulation of meiotic and post-meiotic genes
and proteins in fresh and frozen grafted groups confirmed the progression of
meiosis and post-meiosis in grafted tissues. There were no significant
differences in the expression of apoptosis and necrosis genes between the
grafted and non-grafted control groups. Additionally, no significant
differences were observed between the control and experimental groups in
hormonal assessments.

The optimal hormonal and temperature conditions of the epididymal fat could
support spermatogenesis in grafted immature testicular tissue. This grafting
technique could pave the way for fertility preservation.